Palmyra ( pal-MY-rə; Palmyrene: 𐡶𐡣𐡬𐡥𐡴‎ (), romanized: Tadmor; Arabic: تَدْمُر, romanized: Tadmur) is an ancient city in the eastern part of the Levant, now in the center of modern Syria. Archaeological finds date back to the Neolithic period, and documents first mention the city in the early second millennium BC. Palmyra changed hands on a number of occasions between different empires before becoming a subject of the Roman Empire in the first century AD.

The city grew wealthy from trade caravans; the Palmyrenes became renowned as merchants who established colonies along the Silk Road and operated throughout the Roman Empire. Palmyra's wealth enabled the construction of monumental projects, such as the Great Colonnade, the Temple of Bel, and the distinctive tower tombs. Ethnically, the Palmyrenes combined elements of Amorites, Arameans, and Arabs. Socially structured around kinship and clans, Palmyra's inhabitants spoke Palmyrene Aramaic, a variety of Western Middle Aramaic, while using Koine Greek for commercial and diplomatic purposes. The Hellenistic period of West Asia influenced the culture of Palmyra, which produced distinctive art and architecture that combined different Mediterranean traditions. The city's inhabitants worshiped local Semitic, Mesopotamian, and Arab deities.

By the third century, Palmyra had become a prosperous regional center. It reached the apex of its power in the 260s, when the Palmyrene King Odaenathus defeated the Sasanian emperor Shapur I. The king was succeeded by queen regent Zenobia, who rebelled against Rome and established the Palmyrene Empire. In 273, Roman emperor Aurelian destroyed the city, which was later restored by Diocletian at a reduced size.